Styrofoam is a very useful material, but it’s far from a pretty one. If you’ve got Styrofoam anywhere in your house, or you’re working on a Styrofoam craft project, it’s quite likely that you’ll want to paint it. This will brighten it up and it look more attractive, or could be used to make it unobtrusive if you don’t want it to be visible.
However, you might be wondering how to paint it – since it’s a funny material that incorporates a lot of plastic. A lot of paints struggle to bond to plastic, so you’ll have to choose with care if you’re going to paint Styrofoam. Spray paint is often a great paint because it’s quick to apply and usually creates great results, but can you use it on Styrofoam?
Can you spray paint Styrofoam? You can use some kinds of spray paint on Styrofoam, but you should be aware that any solvents in the paint will dissolve the surface, so you need a suitable spray paint. Water-based acrylic spray paints will work well, and you might find other options that specifically say they are safe for using on Styrofoam.
Can You Put Spray Paint on Styrofoam?
You can put some kinds of spray paint on Styrofoam, yes. Other kinds will simply melt the surface, leaving it pitted and uneven, and ruining its appearance. You must choose a spray paint that specifically says it is safe for use on Styrofoam, or you may completely ruin the project and have to stay from scratch.
Acrylic paints are often the best spray paints for Styrofoam, and indeed these are what you might apply if you were using a brush to paint instead. Choose a color you like, and then test it on a small, inconspicuous area or a scrap of Styrofoam before you start spraying the whole project. This will help you to determine whether it’s safe.
Acrylics have a lot of advantages over other kinds of paints. For example, they are durable and they dry quickly, especially when they are sprayed on instead of applied with a brush.
Do You Have to Sand Styrofoam Before You Paint It?
It’s a good idea to sand Styrofoam before you apply paint to it, as this makes the surface smooth and porous, so the paint will be better able to adhere. You should make sure you wear suitable protection over your mouth and nose when sanding, so you don’t breathe in particles of plastic.
Use a fine-grit sandpaper and work very gently so you don’t tear the Styrofoam as you sand it. Styrofoam is brittle and snaps easily, so you need to be careful throughout the sanding process. Don’t rush it, and don’t sand too heavily. A light rub down should be sufficient in most cases. Your goal is just to remove the surface of the foam.
Once you have sanded it, wipe the whole surface down with a damp cloth, and then you can put down protective cloths and get your spray paint ready.
How Do You Spray Paint Styrofoam?
Start by applying a single, thin layer of spray paint to the Styrofoam, making sure it is even. Do not let the paint pile up, or it may drip, and it won’t adhere properly. Wait for this layer to completely dry, and then add a second layer. Remember you will need to wear protective gear while handling spray paint, and ventilate the space as much as possible.
Once the second layer has dried, it’s generally a good idea to add a third coat if you can. While this might feel like overkill, it ensures you get a good finish and it increases the chances that the paint will stick well. Sometimes, you’ll need fourth and even fifth coats to achieve even coverage.
It’s important to note that spray paint doesn’t stick brilliantly well to Styrofoam, which is why multiple coats are often necessary. If your first coat doesn’t cover the Styrofoam and you can still see white patches, don’t go back and start filling them in before the first coat has dried.
This will cause problems and prevent the paint from drying properly, which will often result in you having to reapply the paint. Instead, let that coat dry and add a second thin coat. Keep adding thin layers until you have got the desired appearance.
How Long Does It Take to Spray Paint Styrofoam?
This is very project-dependent. If you are only painting a small craft project and you only need 3 coats, it will probably take about 3 hours, depending on the paint’s drying time. If you’re painting a wall of Styrofoam insulation, it’s likely to take longer, and may be a day or more.
Different kinds of spray paint have different drying times. Some can be touch dry in as little as 30 minutes. However, it’s best to allow spray paints to dry for around 24 hours if you are applying them to plastic, because this gives them plenty of curing time. Plastics are harder for them to stick to, so this additional time may be important.
Spraying paint onto the surface too soon may cause it to bubble, and could ruin its appearance and adhesion. You shouldn’t rush the drying process, therefore.
Read the instructions on the spray paint can to determine how long it will take to dry, and only start the project once you have calculated how long it should take. Bear in mind that this may vary depending on how many coats you need, so build some leeway into your estimate in case the surface needs multiple coats to get good coverage.
On the whole, spray paint will be faster than your other paint options, but it still needs adequate drying time, or it will bubble and peel.
Final Thoughts
You can spray paint Styrofoam if you use a paint that does not contain solvents that will melt the Styrofoam. Acrylic is most likely to work well, and should stick to the plastic. Remember to apply the paint in thin, even coats so that it sticks properly and achieves good coverage.
